Sperm functional aspects and enriched proteomic pathways of seminal plasma of adult men with obesity

Abstract

BackgroundPrevious studies have demonstrated an association between obesity and the decreased male fertility.Objectiveto observe the mechanisms by which obesity affects semen quality.Materials and methodsA prospective study was performed including 47 male volunteers, of which 27 were obese group (body mass index >30 kg/m2) and 20 were eutrophic (body mass index between 18.5 and 25 kg/m2) controls. Sperm functional analysis was performed. The remaining seminal plasma was pooled—four pools per group— and submitted to proteomic analysis by liquid chromatography coupled to tandem mass spectrometry. Groups were compared by an unpaired Student's t‐test. Differentially expressed proteins were submitted to functional enrichment analysis using the online platform PantherDB.ResultsObese men presented decreased non‐progressive motility, morphology, acrosome integrity, mitochondrial activity, and increased sperm DNA fragmentation. In proteomics analysis, 69 proteins were differentially expressed between the two groups. Among them, one protein was absent, 19 were down‐regulated, 49 were up‐regulated, and one was exclusive in the study group. The main functions enriched were as follows: negative regulation of the intrinsic pathway of apoptosis, activation of immune and inflammatory, antioxidant activity, among others.Conclusionmolecular pathways suggest there is a causative link, and that the effector mechanisms alter sperm metabolic status and defective testicular selection 5 mechanisms.

Male adiposity, sperm parameters and reproductive hormones: An updated systematic review and collaborative meta‐analysis

“…Positive values indicated that the specific unhealthy BMI category has better seminogram parameters than normal weight, whereas negative ES indicates poorer seminogram parameters. In the case of prospective studies, 32 baseline values were used. In most of the cases, these values were directly obtained from the main data of the article (or supplemental data), and in few cases, the values were obtained through a request to the corresponding authors.…”

The Role of Genetics and Oxidative Stress in the Etiology of Male Infertility—A Unifying Hypothesis?

“…As a result, any factors that impact the overall antioxidant status of an individual, and thus the bioavailability of extracellular antioxidants, can have an impact on the levels of oxidative stress suffered by the male germ line and thence fertility ( 180 , 181 ). Examples of such conditions include diet ( 182 ), varicocele ( 183 ) smoking ( 184 ), obesity ( 185 ), heat stress ( 186 ), and environmental toxicants such as bisphenol A ( 187 ) all of which can impact systemic antioxidant tone and thus the vulnerability of spermatozoa to oxidative stress. Inadequate intracellular and extracellular antioxidant protection could therefore be a major factor in the etiology of both male infertility and oxidative DNA damage to the paternal genome ( 188 ).…”

The Vehicle Determines the Destination: The Significance of Seminal Plasma Factors for Male Fertility

“…Proteomics analysis of seminal plasma from obese men revealed 69 proteins differentially expressed, enriched in pathways such as apoptosis, activation of immune and inflammatory responses, and antioxidant activity compared with males with a normal BMI. Simultaneously, sperm in the obesity group presented decreased non-progressive motility and acrosome integrity and increased sperm DNA fragmentation [ 25 ].…”

“…Alterations in distinct pathways can be induced by internal healthy state and external factors. Obesity negatively regulates proteins enriched in the intrinsic pathway of apoptosis, activation of immune and inflammatory responses, and antioxidant activity [ 25 ]. In bilateral varicocele patients, compared with healthy men, pathways involved in response to reactive oxygen species and oxidative stress and tissue homeostasis were affected [ 19 ].…”